Warning when setting empty github-token

[dorzepowski]

Context

To trigger another workflow based on pushed tag with this action, the minimum option is to use Deploy Key.
But to fully leverage the Deploy Key, we need to prevent conventional-changelog-action from using worker Github Token.

To do so, I'm setting an empty string as github-token input.
This works, but running the action with empty string as github-token is raising the warning:

Warning: Can't add secret mask for empty string in ##[add-mask] command.

Expected result

• Description of how to use Deploy Key should be extended with information that github-token must be set to empty string to trigger other workflows on push of tags.
• Setting a github-token input as an empty string shouldn't raise a warning.